Does free will exist?

if not what is the alternative? either every thought action and decicion we ever make is down to random particles on the quantum level or there is some kind of design we cannot calculate (by God, or some similar base universal force). I find both of these options quite disturbing but is there an alternative. every thought or action you, or anything else has is determined by a series of steadily smaller reactions. its bizarre.. if free will is an illusion what are we?